The Art and Market of Castile Soap

Olive oil is a staple in many nations, but especially in Mediterranean cultures. From cooking to soapmaking, olive oil is one of the most versatile natural ingredients found on the market today. The ingredient is so important in traditional soapmaking, that one traditional recipe of soap, Castile soap, named after its origin city in Spain, is made solely with 100% olive oil as the lipid.

The history isn’t completely clear, but it’s believed that Castile soap originated in the early 1500s-1600s as a derivation of Aleppo soap. Aleppo soap is a combination of olive oil and laurel berry oil originating in the Middle-East. It’s believed that the Crusaders brought it back to Europe around the middle 16th century, but because laurel berry oil was native to the Middle East, it was dropped from the recipe when soapmakers in Castile, Spain started crafting it themselves. (Wikipedia.)

Castile soap is a test of fortitude and patience. Soapmaking is already a time-consuming art, as the cold-process method requires soapmakers to wait between four and six weeks of “curing” before the soap is ready to be used. Castile soap takes between six months and one year!

We crafted our first version of Castile soap, With Grace, on April 2, 2017, using a steep water discount and adding sodium lactate. In soapmaking, a water discount means we cut down on the amount of water used in the recipe. This helps to create a harder bar of soap a little faster. Adding sodium lactate, which is a liquid salt derived from the natural fermentation of sugars found in corn and beets (read more on our blog post about sodium in soap), also creates a harder bar of soap. Because Castile soap is 100% olive oil, it can be very mushy and difficult to unmold – the combination of the water discount and sodium lactate make it possible to maintain its shape and still be usable after a nearly six-month curing time.

What makes Castile soap so coveted is the moisturizing properties of olive oil. In cold-process soap, olive oil is often a key ingredient because it is rich in oleic and linoleic acids. These fatty compounds produce conditioning effects when saponified, making a soft, gentle, and stable lather in soap. Therefore, Castile soap is effective for sensitive skin and for babies because of its gentle properties.

Unfortunately, have you noticed the price of olive oil going up in grocery stores? According to USA Today, “The combination of bad weather and pests hit the harvest in Southern Europe, most of all in Italy, where production [of olive oil] is halved from last fall. That’s pushing up Italian wholesale prices by 64% as of mid-February compared with a year earlier, which translates to shelf price increases of 15 to 20% in Italy.” Since the overwhelming majority of olive oil is imported from Italy and Greece to the United States, the prices have significantly jumped, making Castile soap an even more coveted luxury item.

Even with olive oil prices rising, the demand for Castile soap remains high. With such nourishing, moisturizing, skin-loving properties, it’s easy to see why the love for this soap remains 500 years later.